Flexible covers for truck bodies or trailers serve both to protect a load within the trailer or body and to minimize the likelihood of all or part of the load escaping. Because covers for truck bodies or trailers are often large and unwieldy, some form of mechanical assistance is useful to spread and secure the cover over the body or trailer. Truck cover manipulators provide this assistance.
A truck cover manipulator assembly, such as shown in U.S. Pat. No. 3,549,198 to Cappello, generally uses two metal arms powered by a drive mechanism to draw the flexible cover over the trailer or body from one end to the other. As the arms move longitudinally, the arm ends securing one end of the cover move in an arcuate path. When the arms are in a vertical position, they raise the effective height of the truck considerably. Even when an operator is aware that the arms will extend upward, their exact height and amount of obstacle clearance are difficult to estimate visually. This situation is particularly hazardous when a truck cover manipulator assembly is operated near overhead power lines, because the arms of the truck cover manipulator assembly have the potential to contact the power lines and electrocute the operator or damage the truck.
In addition to the risk of electrocution, as the arms swing up and over the trailer or body, the upper portion of the arms are susceptible to bending from the load upon them or from striking an object. The resulting damage to the arms or tie-rod requires expensive and time consuming repair. Thus, the present invention remedies the problems associated with prior truck cover manipulator assemblies by providing both electrical insulation to protect the operator and truck, and segmented arms which permit only the damaged portion of the arm to be replaced.